A conventional driving tool drives a fastener such as a screw into a workpiece. For example, a driving tool disclosed in Japanese Patent Application Publication No. 2007-167986 drives a piston disposed in a cylinder by using a compressed air as a driving source. By the movement of the piston, a screw is driven into a workpiece. At the same time, a part of the compressed air is used as a driving source of a feed piston for feeding the fastener.